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Climate and ENSO Associations with Malaria Incidence in Colombia


Germán Poveda
Postgrado en Aprovechamiento de Recursos Hidráulicos,
Universidad Nacional de Colombia
Medellín, Colombia


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More than five million people live in malaria-prone regions of Colombia. During 1996, transmission of malaria reached 42 cases per 1,000 inhabitants in high-risk areas. The province of Chocó (along the Pacific coast) experienced more than 80,000 cases during 1998 when the population at risk was of 380,000. Malaria is transmitted by mosquito vectors such Anopheles albimanus, A. darlingi and A. nuñeztovari, transmitting Plasmodium falciparum (46.5%) and P. vivax (53.5%). Climate and its variability constitute important factors to explain the incidence of malaria in low-land tropical endemic areas of Colombia. During "normal years", endemic malaria in those regions exhibit a clear-cut "normal" annual cycle, tightly associated with prevalent climatic conditions, mainly mean temperature, precipitation, humidity and river discharges In general, during dry seasons malaria incidence increases concomitant and following periods of reduced rainfall, and river flows, and augmented average and minimum air temperature. (Poveda et al., 2001).

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